This invention relates to a fluid-operated machine, and more particulary to a fluid machine of the type which can be used as a pump or as a fluid motor.
Fluid machines are already known, having two externally meshing gears the shafts of which are mounted in bores of journalling bearings. The meshing gears and the shafts, of which one shaft is usually a drive shaft, are located in a chamber of a housing which is sealingly closed with a cover. This cover has a bore through which the drive shaft passes with a relatively large play. The fluid-operated machines capable of being used as a fluid pump or a fluid motor are usually coupled to an external element, such as for example, a flange of an electromotor in case the fluid-operated machine is a pump. In this instance the drive shaft should be aligned with the aforementioned external element. It is to be noted that the drive shaft mounted without the bearings is not rigid within the housing but is positioned therein with a certain radial play. Since the drive shaft is received within the bore of the cover also with a play it is impossible to easily center the drive shaft with the cover. In the devices known in the prior art, a special additional equipment has been used for centering the drive shaft to the cover sealingly closing the housing of the pump. Such additional equipment, however, is rather expensive and inconvenient in assembling of the pump or motor.